Corpyard cleanup may wait for advanced technology
Shannon Morgan, Berkeley Voice, September 9,1993

Plans to excavate 1,000 cubic yards of contaminated soil at the city's corporation yard this month have been scrapped in favor of removing toxins through new technology.

The city had decided more than three years ago to go ahead with remediation of the soil around underground gasoline storage tank areas in order to comply with Bay Area Regional Water Quality requirements.

But with a cost of $250,000, potential health threats from fumes and disruption to the surrounding residential neighborhood, the Public Works Department and Toxic Management Program are now recommending that the city use a bioventing method to remove the toxins without excavating the soil.

"It's not the least bit disruptive and there's no safety hazards about it. It seems like a much more reasonable approach," said project manager, Jeff Egeberg, manager of engineering.

Under the method, an underground well would placed in the middle of the contaminated soil and would be connected to a pump and blower apparatus the size of an office desk that would sit above ground. The pump would release oxygen into the soil which would then migrate through the soil and activate microorganisms to decompose contaminates into harmless materials.

At a cost of $10 per cubic yard, rather than $250 per cubic yard for excavation, city staff say the method is not only more efficient but would save the city $240,000 if the city council approves the plan later this month.

Egeberg said city staff began to reexamine the issue in light of disruption from 250 truck loads of soil out of the west Berkeley neighborhood, possible health threats to city employees and neighbors from toxic fumes and the requirement to move the city's fleet of maintenance vehicles in order to complete the job.

Area residents, who have been actively pushing for the removal of toxins from their neighborhood for the last two years, have said they would welcome the change of plans, according to community organizer L A Wood.

"The community was concerned about the disruption that would be caused by excavation. We don't want the city to spend $250,000 if they don't have to and it fits into the scheme of what Toxics Management and the Regional Water Quality Board require," Wood said. Wood is one who has worked hard to ensure the removal of contaminates, but also wants to make sure that doing so doesn't cause more harm than good.

"They said there was going to be this odor from excavation with a lot of chemicals floating around in the air, because they were going to pile the soil up and let it the contaminates evaporate before moving it offsite," he said.

While the new method would eliminate air pollution, Wood said he is waiting for a report from the city on its impact. "I wanted to know more about it. The fact that Berkeley has other such systems operating right now is encouraging," he said.

Egeberg confirmed that private industries are using the method as a cheap and effective alternative to moving tons of dirt.

"Alternative methods of treating soil in place have come a long way. We've met with an expert in environmental programs who advised that this is a good candidate of bio-venting," he said.